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81.
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83.
Unknown signals from the fetus are thought to be involved in the onset of parturition. We recently discovered that urinary trypsin inhibitor (UTI) from fetal urine inhibits uterine muscle contraction. Objectives: The aim of this research was to elucidate the mechanism of action of UTI in suppressing cervical maturation. Study design: Non-pregnant and pregnant rabbits pretreated with and without UTI suppositories containing 1000 U (400 μg) for 3 days were treated for 2 days with vaginal suppositories containing 100 ng of interleukin-8 (IL-8). Results: IL-8 induced softening and dilatation of the rabbit cervices. In contrast UTI inhibited IL-8 induced cervical softening and dilatation. Water content, collagen content, neutrophil counts, elastase activity and collagenase activity of the cervix were increased by IL-8, but they did not increase by IL-8 with UTI. Conclusion: These results suggest that UTI inhibits cervical maturation induced by IL-8.  相似文献   
84.
We report an extremely rare case of a gastric duplication cyst together with an aberrant pancreatic ductal system, which communicated with the stomach rather than the pancreatic ductal system with no evidence of pancreatitis. A 46-year-old woman developed severe abdominal pain after a 10-year history of occasional mild abdominal pain. Upper gastrointestinal barium radiography showed a rigidity of the stomach wall, and gastroscopy revealed a fistula orifice at a greater curvature of the gastric body. Subsequent endoscopic suction of mucous secretion from within the fistula provided immediate pain relief. Abdominal computed tomography and ultrasonography showed a cystic mass contiguous with the stomach wall. Surgical exploration revealed an uncommon anomaly of a gastric duplication cyst with the aberrant pancreatic lobe. The patient made an uneventful recovery and remains well 4 years after surgery. We also herein review ten other similar cases of this uncommon congenital anomaly reported in the literature. Received: August 20, 2001 / Accepted: January 8, 2002  相似文献   
85.
To investigate the involvement of protease-activated receptor-2 (PAR-2) in allergic dermatitis, we generated PAR-2-deficient (PAR-2(-/-)) mice. Ear thickness, contact hypersensitivity (CH) induced by topical application of picryl chloride (PC) or oxazolone (Ox) after sensitization, and vascular permeability after ear passive cutaneous anaphylaxis (PCA) were compared between wild-type (WT) and PAR-2(-/-) mice. Ear thickness was almost the same in untreated WT and PAR-2(-/-) mice. Topical application of PC or Ox thickened the ears at 6, 24 and 48 h after challenge with a peak at 24 h in WT mice. In PAR-2(-/-) mice, the ear swelling induced by both PC and Ox was suppressed at every time point, and significant inhibition was found at 24 h in PC-induced CH and at 24 and 48 h in Ox-induced CH. Histopathological observation of the ears at 24 h after challenge revealed that PC- or Ox-induced ear edema and infiltration of inflammatory cells in WT mice were greatly attenuated in PAR-2(-/-) mice. The vascular permeability in the ears after PCA was not different between WT and PAR-2(-/-) mice. These results strongly suggest that PAR-2 plays a crucial role in type IV allergic dermatitis but not in type I allergic dermatitis.  相似文献   
86.
Thyrotropin-releasing hormone (TRH) is best known for its hypothalamic neuroendocrine role in regulating thyroid function. In extra-hypothalamic regions in vitro, we have shown TRH to have a protective effect against synaptic loss and neuronal apoptosis. A role for TRH in Alzheimer's disease (AD) has not been established previously. In this study, we examined the content of the TRH peptide in the hippocampus of elderly controls (n=5) and AD patients (n=7) by radioimmunoassay (RIA). The TRH concentration was decreased in the AD hippocampus compared to normal elderly controls (p < 0.01). In a separate series of experiments utilizing primary cell cultures made from rat hippocampus, TRH peptide concentration was depleted by the addition of TRH antiserum. TRH withdrawal was found to enhance the activity of glycogen synthetase kinase-3 (GSK-3beta), a critical enzyme necessary for the phosphorylation of tau, as well as the phosphorylation of the tau protein itself. This TRH depletion induced upregulation in phosphorylation that was observed to initiate axonal retraction in cultured neurons. These data suggest that TRH within the hippocampus can regulate the activity of various proteins by phosphorylation/dephosphorylation that may be involved in the pathogenesis of AD.  相似文献   
87.
CD19 expression and growth inhibition of tumours in human multiple myeloma   总被引:2,自引:0,他引:2  
Multiple myeloma (MM) is a proliferative disorder of monoclonal plasma cells which accumulate in human bone marrow (BM). CD19 is a hallmark differentiation antigen of the B cell lineage and positively regulates antigen receptor signal transduction in mature B cells. We have previously shown that malignant plasma cells (myeloma cells) isolated from the MM patients lack the CD19 expression, while non-malignant plasma cells isolated from the healthy donors do express the CD19 antigens. It is also intriguing that there exists both CD19- and CD19+ plasma cells in some cases in pre-myeloma states including monoclonal gammopathy of undetermined significance (MGUS). It indicates that MGUS is usually composed of phenotypically non-malignant (CD19+) and malignant (CD19-) plasma cells. Furthermore, we recently demonstrate that, expression of the CD19 gene markedly inhibits the proliferation of human myeloma cell lines in vitro, and exhibits the reduced tumorigenicity in vivo and no anchorage-independent growth in vitro of a tumorigenic myeloma cell line. This inhibitory effect might result from the CD19-mediated intracellular signals because it is not observed in cells expressing the mutant CD19, which lacks the cytoplasmic domain. In this review, we suggest that loss of CD19 in MM could contribute to the proliferative advantage of the malignant plasma cell clones in this disease. Furthermore, we propose the usefulness of the phenotypic analysis of plasma cells in human plasma cell dyscrasia as a new diagnostic tool, and the CD19 gene as a potential target for the gene therapy in MM.  相似文献   
88.
We report a case in which weekly paclitaxel (TXL) administration was effective for gastric cancer with malignant ascites. TXL (80 mg/m2) was infused over 1 hour after short premedication on an outpatient basis. Administration was continued for 3 weeks followed by 1 week rest. The patient was a 49-year-old woman who suffered from non-resectable gastric cancer, staged intraoperatively as having severe lymph node metastasis and malignant ascites. As an outpatient treatment, she was first treated with 5-fluorouracil combined with high-dose Leucovorin for 4 cycles. However, she complained of abdominal fullness and ascites, and received weekly TXL administration as the second line treatment. The ascites had completely disappeared 3 months after administration. The toxic events were anemia (grade 1) and alopecia (grade 2). No major adverse effects such as hypersensitivity reaction, leukopenia or peripheral neuropathy were observed.  相似文献   
89.
Resin acids, a class of wood extractives, are potential toxic constituents in many pulp and paper mill effluents. In the present investigation, the effects of two predominant resin acids, dehydroabietic acid (DHA) and abietic acid (ABA), on survival, reproduction, and growth of the freshwater crustacean Daphnia magna were assessed over its life cycle. Based on the experimentally determined acute toxicity data (48-h EC(50)'s) for DHA (7.48 mg/L) and ABA (7.98 mg/L), D. magna was treated chronically with each resin acid at nominal concentrations of 0, 0.25, 0.5, 1.0, 2.0, 4.0, and 8.0mg/L for 21 days. Both DHA and ABA at concentrations as high as 4.0mg/L did not affect physiological and reproductive parameters such as time to maturation, number of molting, number of broods, and number of offspring produced from surviving daphnids, while significant mortality was observed only at 8.0mg/L in both cases. However, a small but statistically significant decrease in Daphnia growth (body length) at the end of exposure was detected at concentrations as low as 0.5mg/L for DHA and 1.0mg/L for ABA, respectively. These results indicated that both DHA and ABA had the potential to exhibit weak growth inhibition without apparent negative effects on reproduction to D. magna at nonlethal concentration levels. This slight effect is not expected to be ecologically significant because the concentrations of DHA and ABA in biologically treated pulp and paper mill effluents are well below the effective levels observed in the present study.  相似文献   
90.
A 17-year-old man with fracture of the mandible underwent open fixation under general anesthesia. He was an athlete of the rugby suffering the fracture in a match. His preoperative physical examinations were normal except for I degrees atrioventricular block on electrocardiogram (ECG). During anesthesia, atrioventricular dissociation and frequent premature ventricular contractions were induced by the stimulation of nasotracheal intubation and the administration of atropine for the reversal of muscle relaxation. We thought the cause of the arrhythmia is the athlete's heart which may be vagotonic and may induce vagal reflex or fatal arrhythmia. This case demonstrates that it is necessary to pay attention to chronotropic action associated with the intubation of nasopharynx, the handling of laryngoscope and the usage of drugs for the anesthetic management of the athlete.  相似文献   
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